1. Field of the Invention
The present invention relates to a storage control device.
2. Description of the Related Art
Storage control devices comprise a storage section produced by connecting a multiplicity of hard disk drives in the form of an array and provide a host computer (‘host’ hereinbelow) such as a server with a logical storage region (logical volume). In order to increase reliability and so forth, a redundant storage region based on RAID (Redundant Array of Independent Disks) in the storage control device is provided for the host.
Further, data that are to be managed by an enterprise or the like increases on a daily basis. Hence, a storage control device whose storage capacity can be increased in accordance with an increase in data volume is preferable. Further, a storage control device capable of providing a storage region that satisfies the user's needs by connecting a plurality of additional enclosures that provide a storage region to a base enclosure that governs a control function has been proposed (Japanese Application Laid Open No. 2001-339853).
According to the conventional technology that appears in Japanese Application Laid Open No. 2001-339853, the start or stoppage of the supply of power to the base enclosure and the start or stoppage of the supply of power to the respective additional enclosures are linked. As a result, in cases where the storage control device is completely stopped, the supply of power to all of the respective additional enclosures can be automatically stopped simply by stopping the supply of power to the base enclosure.
The respective magnetic disk devices that constitute the RAID group in a different conventional technology according to Japanese Application Laid Open No. 2000-293314 are made to enter sleep mode.
The conventional technology of Japanese Application Laid Open No. 2001-339853 merely links the operation to supply power to the base enclosure and the operation to supply power to the respective additional enclosures and the results of such technology are limited from the standpoint of reducing the amount of power consumption of the storage control device.
On the other hand, in the case of the conventional technology of the Japanese Application Laid Open No. 2000-293314, the amount of power consumption of the storage control device can be reduced because the magnetic disk device is made to enter sleep mode when same has not been accessed for a fixed period.
However, Japanese Application Laid Open No. 2000-293314 leaves room for additional improvement in the area of curtailing the power consumption amount of the respective magnetic disk devices that constitute the RAID group. In other words, even in cases where the respective magnetic disk devices have entered sleep mode, power is supplied to the control circuit section, cooling fan, and power supply circuit in the enclosure such that the operation continues. There is therefore room for improvement with respect to the power consumption amount of each of the parts other than the magnetic disk device.